<html>
	<head>
		<style type="text/css">
			.school-opens {
				width: 250px;           /*元素的宽度*/
				height: 150px;			/*元素的高度*/
				border: 1px solid #000; /*元素的边框*/
				background: url('./school_opens.png') center center no-repeat;
				/*url指定了图片的路径。两个center是指左右和上下居中。no-repeat是指背景图像将仅显示一次，不重复。*/
			}
		</style>
	</head>
	<body>
		<div class="school-opens"></div>
	</body>
</html>